Do inflammatory bowel disease (IBD) patients have a higher prevalence of clinically significant liver disease?
It's a question researchers from Fremantle Hospital's Centre for Inflammatory Bowel Disease and Department of Gastroenterology, along with Curtin University's Centre for Population Health Research, set out to explore in a study to evaluate the claim.
Researchers used transient elastrography for the study, a way of measuring the elastic modulus – or stiffness – of the liver using sonic detection via an ultrasound-like probe in a machine known as a FibroScan.
The liver stiffness is measured in kilopascals, correlated to fibrosis, and is done without invasive investigation to deliver immediate results.
Lead author Dr Lena Thin says it has always been recognised that up to five per cent of IBD patients may have significant liver disease due to many multifactorial causes such as drugs, fatty liver disease and primary sclerosing cholangitis (PSC).
But this may have been over or underestimated due to a reliance on liver biopsies and abnormal liver tests (where liver enzymes are checked and found to be atypical).
IBD patients with Crohn's disease and ulcerative colitis, the two main forms of IBD, were tested (110 total) against 55 in a control group.
There were no significant differences in liver stiffness between the two groups, although age and increased body mass index did independently cause it to be higher in the IBD group.
"The frequency of occult liver disease in IBD patients is low and this was confirmed using transient elastography in this study," Dr Thin says.
"The main cause of liver disease found was thought to be due to fatty liver disease, just as it is in the general population.
"It means we must pay attention to metabolic risk factors in our patients and aim for minimisation of corticosteroid use [steroid hormones]."
Still uncertainty in detection of chloestatic liver diseases
Centre for Inflammatory Bowel Disease director Professor Ian Lawrance, another of the study's authors, says while significant liver disease in the IBD patients was found to be no greater than in the general population, this "may not be fully true" with recent data about PSC.
Dr Thin says this stems from the fact the FibroScan has not been shown to be particularly accurate in predicting fibrosis in chloestatic liver diseases.
"The incidence of PSC in IBD patients may be a lot higher than previously thought," she says.
"Detection of liver injury in IBD using transient elastography." Thin LW, et al. J Crohns Colitis. 2014 Feb 12. pii: S1873-9946(13)00439-X. DOI: 10.1016/j.crohns.2013.12.006. [Epub ahead of print]